/*!	 valuenode_log.cpp
**	 Implementation of the "Natural Logarithm" valuenode conversion.
**
**	Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
**	Copyright (c) 2007, 2008 Chris Moore
**  Copyright (c) 2008, 2011 Carlos López
**
**	This package is free software; you can redistribute it and/or
**	modify it under the terms of the GNU General Public License as
**	published by the Free Software Foundation; either version 2 of
**	the License, or (at your option) any later version.
**
**	This package is distributed in the hope that it will be useful,
**	but WITHOUT ANY WARRANTY; without even the implied warranty of
**	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
**	General Public License for more details.
**
*/

#ifdef USING_PCH
#	include "pch.h"
#else
#ifdef HAVE_CONFIG_H
#	include <config.h>
#endif

#include "valuenode_log.h"
#include "valuenode_const.h"
#include <synfig/general.h>
#include <synfig/localization.h>
#include <synfig/valuenode_registry.h>

#endif

using namespace std;
using namespace etl;
using namespace synfig;

REGISTER_VALUENODE(ValueNode_Logarithm, RELEASE_VERSION_0_61_09, "logarithm", "Logarithm")

ValueNode_Logarithm::ValueNode_Logarithm(const ValueBase &x):
    LinkableValueNode(x.get_type())
{
    Vocab ret(get_children_vocab());
    set_children_vocab(ret);
    Real value(x.get(Real()));
    Real infinity(999999.0);
    Real epsilon(0.000001);

    value = exp(value);

    set_link("link",     ValueNode_Const::create(Real(value)));
    set_link("epsilon",  ValueNode_Const::create(Real(epsilon)));
    set_link("infinite", ValueNode_Const::create(Real(infinity)));
}

ValueNode_Logarithm*
ValueNode_Logarithm::create(const ValueBase &x)
{
    return new ValueNode_Logarithm(x);
}

LinkableValueNode*
ValueNode_Logarithm::create_new()const
{
    return new ValueNode_Logarithm(get_type());
}

ValueNode_Logarithm::~ValueNode_Logarithm()
{
    unlink_all();
}

bool
ValueNode_Logarithm::set_link_vfunc(int i, ValueNode::Handle value)
{
    assert(i >= 0 && i < link_count());

    switch (i) {
    case 0:
        CHECK_TYPE_AND_SET_VALUE(link_,     type_real);

    case 1:
        CHECK_TYPE_AND_SET_VALUE(epsilon_,  type_real);

    case 2:
        CHECK_TYPE_AND_SET_VALUE(infinite_, type_real);
    }

    return false;
}

ValueNode::LooseHandle
ValueNode_Logarithm::get_link_vfunc(int i)const
{
    assert(i >= 0 && i < link_count());

    if (i == 0) {
        return link_;
    }

    if (i == 1) {
        return epsilon_;
    }

    if (i == 2) {
        return infinite_;
    }

    return 0;
}

ValueBase
ValueNode_Logarithm::operator()(Time t)const
{
    if (getenv("SYNFIG_DEBUG_VALUENODE_OPERATORS")) {
        printf("%s:%d operator()\n", __FILE__, __LINE__);
    }

    Real link     = (*link_)(t).get(Real());
    Real epsilon  = (*epsilon_)(t).get(Real());
    Real infinite = (*infinite_)(t).get(Real());

    if (epsilon < 0.00000001) {
        epsilon = 0.00000001;
    }

    if (link < epsilon) {
        return -infinite;
    } else {
        return log(link);
    }
}

bool
ValueNode_Logarithm::check_type(Type &type)
{
    return type == type_real;
}

LinkableValueNode::Vocab
ValueNode_Logarithm::get_children_vocab_vfunc()const
{
    if (children_vocab.size()) {
        return children_vocab;
    }

    LinkableValueNode::Vocab ret;

    ret.push_back(ParamDesc(ValueBase(), "link")
                  .set_local_name(_("Link"))
                  .set_description(_("Value node used to calculate the Neperian logarithm"))
                 );

    ret.push_back(ParamDesc(ValueBase(), "epsilon")
                  .set_local_name(_("Epsilon"))
                  .set_description(_("Value used to compare 'link' with zero "))
                 );

    ret.push_back(ParamDesc(ValueBase(), "infinite")
                  .set_local_name(_("Infinite"))
                  .set_description(_("Returned value when result tends to infinite"))
                 );

    return ret;
}